Allow a socket that connects to reconnect on a periodic basis if it
fails to connect at startup or if the connection drops while in use.
Signed-off-by: Corey Minyard <cminy...@mvista.com>
---
include/sysemu/char.h | 3 ++
qemu-char.c | 88 ++++++++++++++++++++++++++++++++++++++++++++-------
qemu-options.hx | 11 +++++--
3 files changed, 87 insertions(+), 15 deletions(-)
diff --git a/include/sysemu/char.h b/include/sysemu/char.h
index 44baf0f..3d21b5a 100644
--- a/include/sysemu/char.h
+++ b/include/sysemu/char.h
@@ -81,6 +81,9 @@ struct CharDriverState {
guint fd_in_tag;
QemuOpts *opts;
QTAILQ_ENTRY(CharDriverState) next;
+ GSList *backend;
+ QEMUTimer *recon_timer;
+ uint64_t recon_time;
};
/**
diff --git a/qemu-char.c b/qemu-char.c
index dd04cc0..23d7647 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -96,9 +96,22 @@ void qemu_chr_be_event(CharDriverState *s, int event)
/* Keep track if the char device is open */
switch (event) {
case CHR_EVENT_OPENED:
+ if (s->recon_timer) {
+ timer_del(s->recon_timer);
+ }
s->be_open = 1;
break;
case CHR_EVENT_CLOSED:
+ if (s->recon_timer) {
+ void (*chr_close)(struct CharDriverState *chr) = s->chr_close;
+ if (chr_close) {
+ s->chr_close = NULL;
+ chr_close(s);
+ }
+ timer_mod(s->recon_timer,
+ (get_clock() +
+ (s->recon_time * get_ticks_per_sec())));
+ }
s->be_open = 0;
break;
}
@@ -2583,6 +2596,7 @@ static void tcp_chr_close(CharDriverState *chr)
closesocket(s->listen_fd);
}
g_free(s);
+ chr->opaque = NULL;
qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
}
@@ -2642,8 +2656,6 @@ static CharDriverState
*qemu_chr_open_socket_fd(CharDriverState *chr,
chr->get_msgfd = tcp_get_msgfd;
chr->chr_add_client = tcp_chr_add_client;
chr->chr_add_watch = tcp_chr_add_watch;
- /* be isn't opened until we get a connection */
- chr->explicit_be_open = true;
if (is_listen) {
s->listen_fd = fd;
@@ -2681,6 +2693,9 @@ static CharDriverState
*qemu_chr_open_socket(CharDriverState *chr,
bool do_nodelay = !qemu_opt_get_bool(opts, "delay", true);
bool is_unix = qemu_opt_get(opts, "path") != NULL;
+ /* be isn't opened until we get a connection */
+ chr->explicit_be_open = true;
+
if (is_unix) {
if (is_listen) {
fd = unix_listen_opts(opts, &local_err);
@@ -2717,8 +2732,9 @@ static CharDriverState
*qemu_chr_open_socket(CharDriverState *chr,
if (fd >= 0) {
closesocket(fd);
}
- if (chr) {
+ if (chr && chr->opaque) {
g_free(chr->opaque);
+ chr->opaque = NULL;
}
return NULL;
}
@@ -3163,6 +3179,20 @@ void register_char_driver_qapi(const char *name,
ChardevBackendKind kind,
backends = g_slist_append(backends, s);
}
+static void recon_timeout(void *opaque)
+{
+ CharDriverState *chr = opaque;
+ CharDriver *cd = chr->backend->data;
+
+ if (chr->be_open) {
+ return;
+ }
+
+ timer_mod(chr->recon_timer,
+ (get_clock() + (chr->recon_time * get_ticks_per_sec())));
+ cd->open(chr, chr->opts);
+}
+
CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
void (*init)(struct CharDriverState *s),
Error **errp)
@@ -3245,11 +3275,36 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
}
chr = g_malloc0(sizeof(CharDriverState));
- chr = cd->open(chr, opts);
- if (!chr) {
- error_setg(errp, "chardev: opening backend \"%s\" failed",
- qemu_opt_get(opts, "backend"));
- goto err;
+
+ chr->backend = i;
+ chr->recon_time = qemu_opt_get_number(opts, "reconnect", 0);
+ if (chr->recon_time) {
+ if (strcmp(qemu_opt_get(opts, "backend"), "socket") != 0) {
+ g_free(chr);
+ fprintf(stderr, "chardev: reconnect only supported on sockets\n");
+ return NULL;
+ }
+ if (qemu_opt_get_bool(opts, "server", 0)) {
+ g_free(chr);
+ fprintf(stderr, "chardev: server device cannot reconnect\n");
+ return NULL;
+ }
+ chr->opts = opts;
+ chr->recon_timer = timer_new(QEMU_CLOCK_REALTIME, SCALE_NS,
+ recon_timeout, chr);
+
+ /* Make sure it connects in time. */
+ timer_mod(chr->recon_timer,
+ (get_clock() + (chr->recon_time * get_ticks_per_sec())));
+ }
+
+ if (!cd->open(chr, opts)) {
+ if (!chr->recon_time) {
+ /* Reconnect is not enabled, give up */
+ fprintf(stderr, "chardev: opening backend \"%s\" failed\n",
+ qemu_opt_get(opts, "backend"));
+ return NULL;
+ }
}
if (!chr->filename)
@@ -3268,7 +3323,8 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
int len = strlen(qemu_opts_id(opts)) + 6;
base->label = g_malloc(len);
snprintf(base->label, len, "%s-base", qemu_opts_id(opts));
- chr = qemu_chr_open_mux(chr, base);
+ chr = g_malloc0(sizeof(CharDriverState));
+ qemu_chr_open_mux(chr, base);
chr->filename = base->filename;
chr->avail_connections = MAX_MUX;
QTAILQ_INSERT_TAIL(&chardevs, chr, next);
@@ -3276,7 +3332,6 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
chr->avail_connections = 1;
}
chr->label = g_strdup(qemu_opts_id(opts));
- chr->opts = opts;
return chr;
err:
@@ -3372,9 +3427,15 @@ void qemu_chr_fe_release(CharDriverState *s)
void qemu_chr_delete(CharDriverState *chr)
{
+ void (*chr_close)(struct CharDriverState *chr) = chr->chr_close;
+
QTAILQ_REMOVE(&chardevs, chr, next);
- if (chr->chr_close) {
- chr->chr_close(chr);
+ if (chr_close) {
+ chr->chr_close = NULL;
+ chr_close(chr);
+ }
+ if (chr->recon_timer) {
+ timer_free(chr->recon_timer);
}
g_free(chr->filename);
g_free(chr->label);
@@ -3490,6 +3551,9 @@ QemuOptsList qemu_chardev_opts = {
.name = "mux",
.type = QEMU_OPT_BOOL,
},{
+ .name = "reconnect",
+ .type = QEMU_OPT_NUMBER,
+ },{
.name = "signal",
.type = QEMU_OPT_BOOL,
},{
diff --git a/qemu-options.hx b/qemu-options.hx
index 5dc8b75..5bcfaa0 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1780,8 +1780,9 @@ ETEXI
DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
"-chardev null,id=id[,mux=on|off]\n"
"-chardev
socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
- " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
- "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off]
(unix)\n"
+ " [,server][,nowait][,telnet][,mux=on|off][,reconnect=seconds]
(tcp)\n"
+ "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,mux=on|off]\n"
+ " [,reconnect=seconds] (unix)\n"
"-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
" [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
"-chardev msmouse,id=id[,mux=on|off]\n"
@@ -1853,7 +1854,7 @@ Options to each backend are described below.
A void device. This device will not emit any data, and will drop any data it
receives. The null backend does not take any options.
-@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}]
[,server] [,nowait] [,telnet]
+@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}]
[,server] [,nowait] [,telnet] [,reconnect=@var{seconds}]
Create a two-way stream socket, which can be either a TCP or a unix socket. A
unix socket will be created if @option{path} is specified. Behaviour is
@@ -1867,6 +1868,10 @@ connect to a listening socket.
@option{telnet} specifies that traffic on the socket should interpret telnet
escape sequences.
+@option{reconnect} specifies that if the socket does not come up at startup,
+or if the socket is closed for some reason (like the other end exited),
+wait the given number of seconds and attempt to reconnect.
+
TCP and unix socket options are given below:
@table @option
--
1.8.3.1
